granicus.if.org Git - imagemagick/blob - MagickCore/paint.c

   1 /*
   2 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   3 %                                                                             %
   4 %                                                                             %
   5 %                                                                             %
   6 %                      PPPP    AAA   IIIII  N   N  TTTTT                      %
   7 %                      P   P  A   A    I    NN  N    T                        %
   8 %                      PPPP   AAAAA    I    N N N    T                        %
   9 %                      P      A   A    I    N  NN    T                        %
  10 %                      P      A   A  IIIII  N   N    T                        %
  11 %                                                                             %
  12 %                                                                             %
  13 %                        Methods to Paint on an Image                         %
  14 %                                                                             %
  15 %                              Software Design                                %
  16 %                                   Cristy                                    %
  17 %                                 July 1998                                   %
  18 %                                                                             %
  19 %                                                                             %
  20 %  Copyright 1999-2018 ImageMagick Studio LLC, a non-profit organization      %
  21 %  dedicated to making software imaging solutions freely available.           %
  22 %                                                                             %
  23 %  You may not use this file except in compliance with the License.  You may  %
  24 %  obtain a copy of the License at                                            %
  25 %                                                                             %
  26 %    https://www.imagemagick.org/script/license.php                           %
  27 %                                                                             %
  28 %  Unless required by applicable law or agreed to in writing, software        %
  29 %  distributed under the License is distributed on an "AS IS" BASIS,          %
  30 %  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.   %
  31 %  See the License for the specific language governing permissions and        %
  32 %  limitations under the License.                                             %
  33 %                                                                             %
  34 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  35 %
  36 %
  37 */
  38 \f
  39 /*
  40  Include declarations.
  41 */
  42 #include "MagickCore/studio.h"
  43 #include "MagickCore/artifact.h"
  44 #include "MagickCore/channel.h"
  45 #include "MagickCore/color.h"
  46 #include "MagickCore/color-private.h"
  47 #include "MagickCore/colorspace-private.h"
  48 #include "MagickCore/composite.h"
  49 #include "MagickCore/composite-private.h"
  50 #include "MagickCore/draw.h"
  51 #include "MagickCore/draw-private.h"
  52 #include "MagickCore/exception.h"
  53 #include "MagickCore/exception-private.h"
  54 #include "MagickCore/gem.h"
  55 #include "MagickCore/gem-private.h"
  56 #include "MagickCore/monitor.h"
  57 #include "MagickCore/monitor-private.h"
  58 #include "MagickCore/option.h"
  59 #include "MagickCore/paint.h"
  60 #include "MagickCore/pixel-accessor.h"
  61 #include "MagickCore/resource_.h"
  62 #include "MagickCore/statistic.h"
  63 #include "MagickCore/string_.h"
  64 #include "MagickCore/string-private.h"
  65 #include "MagickCore/thread-private.h"
  66 \f
  67 /*
  68 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  69 %                                                                             %
  70 %                                                                             %
  71 %                                                                             %
  72 %   F l o o d f i l l P a i n t I m a g e                                     %
  73 %                                                                             %
  74 %                                                                             %
  75 %                                                                             %
  76 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  77 %
  78 %  FloodfillPaintImage() changes the color value of any pixel that matches
  79 %  target and is an immediate neighbor.  If the method FillToBorderMethod is
  80 %  specified, the color value is changed for any neighbor pixel that does not
  81 %  match the bordercolor member of image.
  82 %
  83 %  By default target must match a particular pixel color exactly.  However,
  84 %  in many cases two colors may differ by a small amount.  The fuzz member of
  85 %  image defines how much tolerance is acceptable to consider two colors as
  86 %  the same.  For example, set fuzz to 10 and the color red at intensities of
  87 %  100 and 102 respectively are now interpreted as the same color for the
  88 %  purposes of the floodfill.
  89 %
  90 %  The format of the FloodfillPaintImage method is:
  91 %
  92 %      MagickBooleanType FloodfillPaintImage(Image *image,
  93 %        const DrawInfo *draw_info,const PixelInfo target,
  94 %        const ssize_t x_offset,const ssize_t y_offset,
  95 %        const MagickBooleanType invert,ExceptionInfo *exception)
  96 %
  97 %  A description of each parameter follows:
  98 %
  99 %    o image: the image.
 100 %
 101 %    o draw_info: the draw info.
 102 %
 103 %    o target: the RGB value of the target color.
 104 %
 105 %    o x_offset,y_offset: the starting location of the operation.
 106 %
 107 %    o invert: paint any pixel that does not match the target color.
 108 %
 109 %    o exception: return any errors or warnings in this structure.
 110 %
 111 */
 112 MagickExport MagickBooleanType FloodfillPaintImage(Image *image,
 113   const DrawInfo *draw_info,const PixelInfo *target,const ssize_t x_offset,
 114   const ssize_t y_offset,const MagickBooleanType invert,
 115   ExceptionInfo *exception)
 116 {
 117 #define MaxStacksize  524288UL
 118 #define PushSegmentStack(up,left,right,delta) \
 119 { \
 120   if (s >= (segment_stack+MaxStacksize)) \
 121     ThrowBinaryException(DrawError,"SegmentStackOverflow",image->filename) \
 122   else \
 123     { \
 124       if ((((up)+(delta)) >= 0) && (((up)+(delta)) < (ssize_t) image->rows)) \
 125         { \
 126           s->x1=(double) (left); \
 127           s->y1=(double) (up); \
 128           s->x2=(double) (right); \
 129           s->y2=(double) (delta); \
 130           s++; \
 131         } \
 132     } \
 133 }
 134
 135   CacheView
 136     *floodplane_view,
 137     *image_view;
 138
 139   Image
 140     *floodplane_image;
 141
 142   MagickBooleanType
 143     skip,
 144     status;
 145
 146   MemoryInfo
 147     *segment_info;
 148
 149   PixelInfo
 150     fill_color,
 151     pixel;
 152
 153   register SegmentInfo
 154     *s;
 155
 156   SegmentInfo
 157     *segment_stack;
 158
 159   ssize_t
 160     offset,
 161     start,
 162     x1,
 163     x2,
 164     y;
 165
 166   /*
 167     Check boundary conditions.
 168   */
 169   assert(image != (Image *) NULL);
 170   assert(image->signature == MagickCoreSignature);
 171   if (image->debug != MagickFalse)
 172     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
 173   assert(draw_info != (DrawInfo *) NULL);
 174   assert(draw_info->signature == MagickCoreSignature);
 175   if ((x_offset < 0) || (x_offset >= (ssize_t) image->columns))
 176     return(MagickFalse);
 177   if ((y_offset < 0) || (y_offset >= (ssize_t) image->rows))
 178     return(MagickFalse);
 179   if (SetImageStorageClass(image,DirectClass,exception) == MagickFalse)
 180     return(MagickFalse);
 181   if (IsGrayColorspace(image->colorspace) != MagickFalse)
 182     (void) SetImageColorspace(image,sRGBColorspace,exception);
 183   if ((image->alpha_trait == UndefinedPixelTrait) &&
 184       (draw_info->fill.alpha_trait != UndefinedPixelTrait))
 185     (void) SetImageAlpha(image,OpaqueAlpha,exception);
 186   /*
 187     Set floodfill state.
 188   */
 189   floodplane_image=CloneImage(image,0,0,MagickTrue,
 190     exception);
 191   if (floodplane_image == (Image *) NULL)
 192     return(MagickFalse);
 193   floodplane_image->alpha_trait=UndefinedPixelTrait;
 194   floodplane_image->colorspace=GRAYColorspace;
 195   (void) QueryColorCompliance("#000",AllCompliance,
 196     &floodplane_image->background_color,exception);
 197   (void) SetImageBackgroundColor(floodplane_image,exception);
 198   segment_info=AcquireVirtualMemory(MaxStacksize,sizeof(*segment_stack));
 199   if (segment_info == (MemoryInfo *) NULL)
 200     {
 201       floodplane_image=DestroyImage(floodplane_image);
 202       ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
 203         image->filename);
 204     }
 205   segment_stack=(SegmentInfo *) GetVirtualMemoryBlob(segment_info);
 206   /*
 207     Push initial segment on stack.
 208   */
 209   status=MagickTrue;
 210   start=0;
 211   s=segment_stack;
 212   PushSegmentStack(y_offset,x_offset,x_offset,1);
 213   PushSegmentStack(y_offset+1,x_offset,x_offset,-1);
 214   GetPixelInfo(image,&pixel);
 215   image_view=AcquireVirtualCacheView(image,exception);
 216   floodplane_view=AcquireAuthenticCacheView(floodplane_image,exception);
 217   while (s > segment_stack)
 218   {
 219     register const Quantum
 220       *magick_restrict p;
 221
 222     register Quantum
 223       *magick_restrict q;
 224
 225     register ssize_t
 226       x;
 227
 228     /*
 229       Pop segment off stack.
 230     */
 231     s--;
 232     x1=(ssize_t) s->x1;
 233     x2=(ssize_t) s->x2;
 234     offset=(ssize_t) s->y2;
 235     y=(ssize_t) s->y1+offset;
 236     /*
 237       Recolor neighboring pixels.
 238     */
 239     p=GetCacheViewVirtualPixels(image_view,0,y,(size_t) (x1+1),1,exception);
 240     q=GetCacheViewAuthenticPixels(floodplane_view,0,y,(size_t) (x1+1),1,
 241       exception);
 242     if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
 243       break;
 244     p+=x1*GetPixelChannels(image);
 245     q+=x1*GetPixelChannels(floodplane_image);
 246     for (x=x1; x >= 0; x--)
 247     {
 248       if (GetPixelGray(floodplane_image,q) != 0)
 249         break;
 250       GetPixelInfoPixel(image,p,&pixel);
 251       if (IsFuzzyEquivalencePixelInfo(&pixel,target) == invert)
 252         break;
 253       SetPixelGray(floodplane_image,QuantumRange,q);
 254       p-=GetPixelChannels(image);
 255       q-=GetPixelChannels(floodplane_image);
 256     }
 257     if (SyncCacheViewAuthenticPixels(floodplane_view,exception) == MagickFalse)
 258       break;
 259     skip=x >= x1 ? MagickTrue : MagickFalse;
 260     if (skip == MagickFalse)
 261       {
 262         start=x+1;
 263         if (start < x1)
 264           PushSegmentStack(y,start,x1-1,-offset);
 265         x=x1+1;
 266       }
 267     do
 268     {
 269       if (skip == MagickFalse)
 270         {
 271           if (x < (ssize_t) image->columns)
 272             {
 273               p=GetCacheViewVirtualPixels(image_view,x,y,image->columns-x,1,
 274                 exception);
 275               q=GetCacheViewAuthenticPixels(floodplane_view,x,y,image->columns-
 276                 x,1,exception);
 277               if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
 278                 break;
 279               for ( ; x < (ssize_t) image->columns; x++)
 280               {
 281                 if (GetPixelGray(floodplane_image,q) != 0)
 282                   break;
 283                 GetPixelInfoPixel(image,p,&pixel);
 284                 if (IsFuzzyEquivalencePixelInfo(&pixel,target) == invert)
 285                   break;
 286                 SetPixelGray(floodplane_image,QuantumRange,q);
 287                 p+=GetPixelChannels(image);
 288                 q+=GetPixelChannels(floodplane_image);
 289               }
 290               status=SyncCacheViewAuthenticPixels(floodplane_view,exception);
 291               if (status == MagickFalse)
 292                 break;
 293             }
 294           PushSegmentStack(y,start,x-1,offset);
 295           if (x > (x2+1))
 296             PushSegmentStack(y,x2+1,x-1,-offset);
 297         }
 298       skip=MagickFalse;
 299       x++;
 300       if (x <= x2)
 301         {
 302           p=GetCacheViewVirtualPixels(image_view,x,y,(size_t) (x2-x+1),1,
 303             exception);
 304           q=GetCacheViewAuthenticPixels(floodplane_view,x,y,(size_t) (x2-x+1),1,
 305             exception);
 306           if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
 307             break;
 308           for ( ; x <= x2; x++)
 309           {
 310             if (GetPixelGray(floodplane_image,q) != 0)
 311               break;
 312             GetPixelInfoPixel(image,p,&pixel);
 313             if (IsFuzzyEquivalencePixelInfo(&pixel,target) != invert)
 314               break;
 315             p+=GetPixelChannels(image);
 316             q+=GetPixelChannels(floodplane_image);
 317           }
 318         }
 319       start=x;
 320     } while (x <= x2);
 321   }
 322   status=MagickTrue;
 323   for (y=0; y < (ssize_t) image->rows; y++)
 324   {
 325     register const Quantum
 326       *magick_restrict p;
 327
 328     register Quantum
 329       *magick_restrict q;
 330
 331     register ssize_t
 332       x;
 333
 334     /*
 335       Tile fill color onto floodplane.
 336     */
 337     if (status == MagickFalse)
 338       continue;
 339     p=GetCacheViewVirtualPixels(floodplane_view,0,y,image->columns,1,exception);
 340     q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
 341     if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
 342       {
 343         status=MagickFalse;
 344         continue;
 345       }
 346     for (x=0; x < (ssize_t) image->columns; x++)
 347     {
 348       if (GetPixelGray(floodplane_image,p) != 0)
 349         {
 350           GetFillColor(draw_info,x,y,&fill_color,exception);
 351           SetPixelViaPixelInfo(image,&fill_color,q);
 352         }
 353       p+=GetPixelChannels(floodplane_image);
 354       q+=GetPixelChannels(image);
 355     }
 356     if (SyncCacheViewAuthenticPixels(image_view,exception) == MagickFalse)
 357       status=MagickFalse;
 358   }
 359   floodplane_view=DestroyCacheView(floodplane_view);
 360   image_view=DestroyCacheView(image_view);
 361   segment_info=RelinquishVirtualMemory(segment_info);
 362   floodplane_image=DestroyImage(floodplane_image);
 363   return(status);
 364 }
 365 \f
 366 /*
 367 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 368 %                                                                             %
 369 %                                                                             %
 370 %                                                                             %
 371 +     G r a d i e n t I m a g e                                               %
 372 %                                                                             %
 373 %                                                                             %
 374 %                                                                             %
 375 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 376 %
 377 %  GradientImage() applies a continuously smooth color transitions along a
 378 %  vector from one color to another.
 379 %
 380 %  Note, the interface of this method will change in the future to support
 381 %  more than one transistion.
 382 %
 383 %  The format of the GradientImage method is:
 384 %
 385 %      MagickBooleanType GradientImage(Image *image,const GradientType type,
 386 %        const SpreadMethod method,const PixelInfo *start_color,
 387 %        const PixelInfo *stop_color,ExceptionInfo *exception)
 388 %
 389 %  A description of each parameter follows:
 390 %
 391 %    o image: the image.
 392 %
 393 %    o type: the gradient type: linear or radial.
 394 %
 395 %    o spread: the gradient spread meathod: pad, reflect, or repeat.
 396 %
 397 %    o start_color: the start color.
 398 %
 399 %    o stop_color: the stop color.
 400 %
 401 %    o exception: return any errors or warnings in this structure.
 402 %
 403 */
 404 MagickExport MagickBooleanType GradientImage(Image *image,
 405   const GradientType type,const SpreadMethod method,const StopInfo *stops,
 406   const size_t number_stops,ExceptionInfo *exception)
 407 {
 408   const char
 409     *artifact;
 410
 411   DrawInfo
 412     *draw_info;
 413
 414   GradientInfo
 415     *gradient;
 416
 417   MagickBooleanType
 418     status;
 419
 420   /*
 421     Set gradient start-stop end points.
 422   */
 423   assert(image != (const Image *) NULL);
 424   assert(image->signature == MagickCoreSignature);
 425   if (image->debug != MagickFalse)
 426     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
 427   assert(stops != (const StopInfo *) NULL);
 428   assert(number_stops > 0);
 429   draw_info=AcquireDrawInfo();
 430   gradient=(&draw_info->gradient);
 431   gradient->type=type;
 432   gradient->bounding_box.width=image->columns;
 433   gradient->bounding_box.height=image->rows;
 434   artifact=GetImageArtifact(image,"gradient:bounding-box");
 435   if (artifact != (const char *) NULL)
 436     (void) ParseAbsoluteGeometry(artifact,&gradient->bounding_box);
 437   gradient->gradient_vector.x2=(double) image->columns-1;
 438   gradient->gradient_vector.y2=(double) image->rows-1;
 439   artifact=GetImageArtifact(image,"gradient:direction");
 440   if (artifact != (const char *) NULL)
 441     {
 442       GravityType
 443         direction;
 444
 445       direction=(GravityType) ParseCommandOption(MagickGravityOptions,
 446         MagickFalse,artifact);
 447       switch (direction)
 448       {
 449         case NorthWestGravity:
 450         {
 451           gradient->gradient_vector.x1=(double) image->columns-1;
 452           gradient->gradient_vector.y1=(double) image->rows-1;
 453           gradient->gradient_vector.x2=0.0;
 454           gradient->gradient_vector.y2=0.0;
 455           break;
 456         }
 457         case NorthGravity:
 458         {
 459           gradient->gradient_vector.x1=0.0;
 460           gradient->gradient_vector.y1=(double) image->rows-1;
 461           gradient->gradient_vector.x2=0.0;
 462           gradient->gradient_vector.y2=0.0;
 463           break;
 464         }
 465         case NorthEastGravity:
 466         {
 467           gradient->gradient_vector.x1=0.0;
 468           gradient->gradient_vector.y1=(double) image->rows-1;
 469           gradient->gradient_vector.x2=(double) image->columns-1;
 470           gradient->gradient_vector.y2=0.0;
 471           break;
 472         }
 473         case WestGravity:
 474         {
 475           gradient->gradient_vector.x1=(double) image->columns-1;
 476           gradient->gradient_vector.y1=0.0;
 477           gradient->gradient_vector.x2=0.0;
 478           gradient->gradient_vector.y2=0.0;
 479           break;
 480         }
 481         case EastGravity:
 482         {
 483           gradient->gradient_vector.x1=0.0;
 484           gradient->gradient_vector.y1=0.0;
 485           gradient->gradient_vector.x2=(double) image->columns-1;
 486           gradient->gradient_vector.y2=0.0;
 487           break;
 488         }
 489         case SouthWestGravity:
 490         {
 491           gradient->gradient_vector.x1=(double) image->columns-1;
 492           gradient->gradient_vector.y1=0.0;
 493           gradient->gradient_vector.x2=0.0;
 494           gradient->gradient_vector.y2=(double) image->rows-1;
 495           break;
 496         }
 497         case SouthGravity:
 498         {
 499           gradient->gradient_vector.x1=0.0;
 500           gradient->gradient_vector.y1=0.0;
 501           gradient->gradient_vector.x2=0.0;
 502           gradient->gradient_vector.y2=(double) image->columns-1;
 503           break;
 504         }
 505         case SouthEastGravity:
 506         {
 507           gradient->gradient_vector.x1=0.0;
 508           gradient->gradient_vector.y1=0.0;
 509           gradient->gradient_vector.x2=(double) image->columns-1;
 510           gradient->gradient_vector.y2=(double) image->rows-1;
 511           break;
 512         }
 513         default:
 514           break;
 515       }
 516     }
 517   artifact=GetImageArtifact(image,"gradient:angle");
 518   if (artifact != (const char *) NULL)
 519     gradient->angle=StringToDouble(artifact,(char **) NULL);
 520   artifact=GetImageArtifact(image,"gradient:vector");
 521   if (artifact != (const char *) NULL)
 522     (void) sscanf(artifact,"%lf%*[ ,]%lf%*[ ,]%lf%*[ ,]%lf",
 523       &gradient->gradient_vector.x1,&gradient->gradient_vector.y1,
 524       &gradient->gradient_vector.x2,&gradient->gradient_vector.y2);
 525   if ((GetImageArtifact(image,"gradient:angle") == (const char *) NULL) &&
 526       (GetImageArtifact(image,"gradient:direction") == (const char *) NULL) &&
 527       (GetImageArtifact(image,"gradient:extent") == (const char *) NULL) &&
 528       (GetImageArtifact(image,"gradient:vector") == (const char *) NULL))
 529     if ((type == LinearGradient) && (gradient->gradient_vector.y2 != 0.0))
 530       gradient->gradient_vector.x2=0.0;
 531   gradient->center.x=(double) gradient->gradient_vector.x2/2.0;
 532   gradient->center.y=(double) gradient->gradient_vector.y2/2.0;
 533   artifact=GetImageArtifact(image,"gradient:center");
 534   if (artifact != (const char *) NULL)
 535     (void) sscanf(artifact,"%lf%*[ ,]%lf",&gradient->center.x,
 536       &gradient->center.y);
 537   artifact=GetImageArtifact(image,"gradient:angle");
 538   if ((type == LinearGradient) && (artifact != (const char *) NULL))
 539     {
 540       double
 541         sine,
 542         cosine,
 543         distance;
 544
 545       /*
 546         Reference https://drafts.csswg.org/css-images-3/#linear-gradients.
 547       */
 548       sine=sin((double) DegreesToRadians(gradient->angle-90.0));
 549       cosine=cos((double) DegreesToRadians(gradient->angle-90.0));
 550       distance=fabs((double) (image->columns-1.0)*cosine)+
 551         fabs((double) (image->rows-1.0)*sine);
 552       gradient->gradient_vector.x1=0.5*((image->columns-1.0)-distance*cosine);
 553       gradient->gradient_vector.y1=0.5*((image->rows-1.0)-distance*sine);
 554       gradient->gradient_vector.x2=0.5*((image->columns-1.0)+distance*cosine);
 555       gradient->gradient_vector.y2=0.5*((image->rows-1.0)+distance*sine);
 556     }
 557   gradient->radii.x=(double) MagickMax((image->columns-1.0),(image->rows-1.0))/
 558     2.0;
 559   gradient->radii.y=gradient->radii.x;
 560   artifact=GetImageArtifact(image,"gradient:extent");
 561   if (artifact != (const char *) NULL)
 562     {
 563       if (LocaleCompare(artifact,"Circle") == 0)
 564         {
 565           gradient->radii.x=(double) MagickMax((image->columns-1.0),
 566             (image->rows-1.0))/2.0;
 567           gradient->radii.y=gradient->radii.x;
 568         }
 569       if (LocaleCompare(artifact,"Diagonal") == 0)
 570         {
 571           gradient->radii.x=(double) (sqrt((double) (image->columns-1.0)*
 572             (image->columns-1.0)+(image->rows-1.0)*(image->rows-1.0)))/2.0;
 573           gradient->radii.y=gradient->radii.x;
 574         }
 575       if (LocaleCompare(artifact,"Ellipse") == 0)
 576         {
 577           gradient->radii.x=(double) (image->columns-1.0)/2.0;
 578           gradient->radii.y=(double) (image->rows-1.0)/2.0;
 579         }
 580       if (LocaleCompare(artifact,"Maximum") == 0)
 581         {
 582           gradient->radii.x=(double) MagickMax((image->columns-1.0),
 583             (image->rows-1.0))/2.0;
 584           gradient->radii.y=gradient->radii.x;
 585         }
 586       if (LocaleCompare(artifact,"Minimum") == 0)
 587         {
 588           gradient->radii.x=(double) (MagickMin((image->columns-1.0),
 589             (image->rows-1.0)))/2.0;
 590           gradient->radii.y=gradient->radii.x;
 591         }
 592     }
 593   artifact=GetImageArtifact(image,"gradient:radii");
 594   if (artifact != (const char *) NULL)
 595     (void) sscanf(artifact,"%lf%*[ ,]%lf",&gradient->radii.x,
 596       &gradient->radii.y);
 597   gradient->radius=MagickMax(gradient->radii.x,gradient->radii.y);
 598   gradient->spread=method;
 599   /*
 600     Define the gradient to fill between the stops.
 601   */
 602   gradient->number_stops=number_stops;
 603   gradient->stops=(StopInfo *) AcquireQuantumMemory(gradient->number_stops,
 604     sizeof(*gradient->stops));
 605   if (gradient->stops == (StopInfo *) NULL)
 606     ThrowBinaryException(ResourceLimitError,"MemoryAllocationFailed",
 607       image->filename);
 608   (void) memcpy(gradient->stops,stops,(size_t) number_stops*
 609     sizeof(*stops));
 610   /*
 611     Draw a gradient on the image.
 612   */
 613   status=DrawGradientImage(image,draw_info,exception);
 614   draw_info=DestroyDrawInfo(draw_info);
 615   return(status);
 616 }
 617 \f
 618 /*
 619 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 620 %                                                                             %
 621 %                                                                             %
 622 %                                                                             %
 623 %     O i l P a i n t I m a g e                                               %
 624 %                                                                             %
 625 %                                                                             %
 626 %                                                                             %
 627 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 628 %
 629 %  OilPaintImage() applies a special effect filter that simulates an oil
 630 %  painting.  Each pixel is replaced by the most frequent color occurring
 631 %  in a circular region defined by radius.
 632 %
 633 %  The format of the OilPaintImage method is:
 634 %
 635 %      Image *OilPaintImage(const Image *image,const double radius,
 636 %        const double sigma,ExceptionInfo *exception)
 637 %
 638 %  A description of each parameter follows:
 639 %
 640 %    o image: the image.
 641 %
 642 %    o radius: the radius of the circular neighborhood.
 643 %
 644 %    o sigma: the standard deviation of the Gaussian, in pixels.
 645 %
 646 %    o exception: return any errors or warnings in this structure.
 647 %
 648 */
 649
 650 static size_t **DestroyHistogramThreadSet(size_t **histogram)
 651 {
 652   register ssize_t
 653     i;
 654
 655   assert(histogram != (size_t **) NULL);
 656   for (i=0; i < (ssize_t) GetMagickResourceLimit(ThreadResource); i++)
 657     if (histogram[i] != (size_t *) NULL)
 658       histogram[i]=(size_t *) RelinquishMagickMemory(histogram[i]);
 659   histogram=(size_t **) RelinquishMagickMemory(histogram);
 660   return(histogram);
 661 }
 662
 663 static size_t **AcquireHistogramThreadSet(const size_t count)
 664 {
 665   register ssize_t
 666     i;
 667
 668   size_t
 669     **histogram,
 670     number_threads;
 671
 672   number_threads=(size_t) GetMagickResourceLimit(ThreadResource);
 673   histogram=(size_t **) AcquireQuantumMemory(number_threads,sizeof(*histogram));
 674   if (histogram == (size_t **) NULL)
 675     return((size_t **) NULL);
 676   (void) memset(histogram,0,number_threads*sizeof(*histogram));
 677   for (i=0; i < (ssize_t) number_threads; i++)
 678   {
 679     histogram[i]=(size_t *) AcquireQuantumMemory(count,sizeof(**histogram));
 680     if (histogram[i] == (size_t *) NULL)
 681       return(DestroyHistogramThreadSet(histogram));
 682   }
 683   return(histogram);
 684 }
 685
 686 MagickExport Image *OilPaintImage(const Image *image,const double radius,
 687   const double sigma,ExceptionInfo *exception)
 688 {
 689 #define NumberPaintBins  256
 690 #define OilPaintImageTag  "OilPaint/Image"
 691
 692   CacheView
 693     *image_view,
 694     *paint_view;
 695
 696   Image
 697     *linear_image,
 698     *paint_image;
 699
 700   MagickBooleanType
 701     status;
 702
 703   MagickOffsetType
 704     progress;
 705
 706   size_t
 707     **histograms,
 708     width;
 709
 710   ssize_t
 711     center,
 712     y;
 713
 714   /*
 715     Initialize painted image attributes.
 716   */
 717   assert(image != (const Image *) NULL);
 718   assert(image->signature == MagickCoreSignature);
 719   if (image->debug != MagickFalse)
 720     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
 721   assert(exception != (ExceptionInfo *) NULL);
 722   assert(exception->signature == MagickCoreSignature);
 723   width=GetOptimalKernelWidth2D(radius,sigma);
 724   linear_image=CloneImage(image,0,0,MagickTrue,exception);
 725   paint_image=CloneImage(image,0,0,MagickTrue,exception);
 726   if ((linear_image == (Image *) NULL) || (paint_image == (Image *) NULL))
 727     {
 728       if (linear_image != (Image *) NULL)
 729         linear_image=DestroyImage(linear_image);
 730       if (paint_image != (Image *) NULL)
 731         linear_image=DestroyImage(paint_image);
 732       return((Image *) NULL);
 733     }
 734   if (SetImageStorageClass(paint_image,DirectClass,exception) == MagickFalse)
 735     {
 736       linear_image=DestroyImage(linear_image);
 737       paint_image=DestroyImage(paint_image);
 738       return((Image *) NULL);
 739     }
 740   histograms=AcquireHistogramThreadSet(NumberPaintBins);
 741   if (histograms == (size_t **) NULL)
 742     {
 743       linear_image=DestroyImage(linear_image);
 744       paint_image=DestroyImage(paint_image);
 745       ThrowImageException(ResourceLimitError,"MemoryAllocationFailed");
 746     }
 747   /*
 748     Oil paint image.
 749   */
 750   status=MagickTrue;
 751   progress=0;
 752   center=(ssize_t) GetPixelChannels(linear_image)*(linear_image->columns+width)*
 753     (width/2L)+GetPixelChannels(linear_image)*(width/2L);
 754   image_view=AcquireVirtualCacheView(linear_image,exception);
 755   paint_view=AcquireAuthenticCacheView(paint_image,exception);
 756 #if defined(MAGICKCORE_OPENMP_SUPPORT)
 757   #pragma omp parallel for schedule(static) shared(progress,status) \
 758     magick_number_threads(linear_image,paint_image,linear_image->rows,1)
 759 #endif
 760   for (y=0; y < (ssize_t) linear_image->rows; y++)
 761   {
 762     register const Quantum
 763       *magick_restrict p;
 764
 765     register Quantum
 766       *magick_restrict q;
 767
 768     register size_t
 769       *histogram;
 770
 771     register ssize_t
 772       x;
 773
 774     if (status == MagickFalse)
 775       continue;
 776     p=GetCacheViewVirtualPixels(image_view,-((ssize_t) width/2L),y-(ssize_t)
 777       (width/2L),linear_image->columns+width,width,exception);
 778     q=QueueCacheViewAuthenticPixels(paint_view,0,y,paint_image->columns,1,
 779       exception);
 780     if ((p == (const Quantum *) NULL) || (q == (Quantum *) NULL))
 781       {
 782         status=MagickFalse;
 783         continue;
 784       }
 785     histogram=histograms[GetOpenMPThreadId()];
 786     for (x=0; x < (ssize_t) linear_image->columns; x++)
 787     {
 788       register ssize_t
 789         i,
 790         u;
 791
 792       size_t
 793         count;
 794
 795       ssize_t
 796         j,
 797         k,
 798         n,
 799         v;
 800
 801       /*
 802         Assign most frequent color.
 803       */
 804       k=0;
 805       j=0;
 806       count=0;
 807       (void) memset(histogram,0,NumberPaintBins* sizeof(*histogram));
 808       for (v=0; v < (ssize_t) width; v++)
 809       {
 810         for (u=0; u < (ssize_t) width; u++)
 811         {
 812           n=(ssize_t) ScaleQuantumToChar(ClampToQuantum(GetPixelIntensity(
 813             linear_image,p+GetPixelChannels(linear_image)*(u+k))));
 814           histogram[n]++;
 815           if (histogram[n] > count)
 816             {
 817               j=k+u;
 818               count=histogram[n];
 819             }
 820         }
 821         k+=(ssize_t) (linear_image->columns+width);
 822       }
 823       for (i=0; i < (ssize_t) GetPixelChannels(linear_image); i++)
 824       {
 825         PixelChannel channel = GetPixelChannelChannel(linear_image,i);
 826         PixelTrait traits = GetPixelChannelTraits(linear_image,channel);
 827         PixelTrait paint_traits=GetPixelChannelTraits(paint_image,channel);
 828         if ((traits == UndefinedPixelTrait) ||
 829             (paint_traits == UndefinedPixelTrait))
 830           continue;
 831         if ((paint_traits & CopyPixelTrait) != 0)
 832           {
 833             SetPixelChannel(paint_image,channel,p[center+i],q);
 834             continue;
 835           }
 836         SetPixelChannel(paint_image,channel,p[j*GetPixelChannels(linear_image)+
 837           i],q);
 838       }
 839       p+=GetPixelChannels(linear_image);
 840       q+=GetPixelChannels(paint_image);
 841     }
 842     if (SyncCacheViewAuthenticPixels(paint_view,exception) == MagickFalse)
 843       status=MagickFalse;
 844     if (linear_image->progress_monitor != (MagickProgressMonitor) NULL)
 845       {
 846         MagickBooleanType
 847           proceed;
 848
 849 #if defined(MAGICKCORE_OPENMP_SUPPORT)
 850         #pragma omp critical (MagickCore_OilPaintImage)
 851 #endif
 852         proceed=SetImageProgress(linear_image,OilPaintImageTag,progress++,
 853           linear_image->rows);
 854         if (proceed == MagickFalse)
 855           status=MagickFalse;
 856       }
 857   }
 858   paint_view=DestroyCacheView(paint_view);
 859   image_view=DestroyCacheView(image_view);
 860   histograms=DestroyHistogramThreadSet(histograms);
 861   linear_image=DestroyImage(linear_image);
 862   if (status == MagickFalse)
 863     paint_image=DestroyImage(paint_image);
 864   return(paint_image);
 865 }
 866 \f
 867 /*
 868 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 869 %                                                                             %
 870 %                                                                             %
 871 %                                                                             %
 872 %     O p a q u e P a i n t I m a g e                                         %
 873 %                                                                             %
 874 %                                                                             %
 875 %                                                                             %
 876 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 877 %
 878 %  OpaquePaintImage() changes any pixel that matches color with the color
 879 %  defined by fill argument.
 880 %
 881 %  By default color must match a particular pixel color exactly.  However, in
 882 %  many cases two colors may differ by a small amount.  Fuzz defines how much
 883 %  tolerance is acceptable to consider two colors as the same.  For example,
 884 %  set fuzz to 10 and the color red at intensities of 100 and 102 respectively
 885 %  are now interpreted as the same color.
 886 %
 887 %  The format of the OpaquePaintImage method is:
 888 %
 889 %      MagickBooleanType OpaquePaintImage(Image *image,const PixelInfo *target,
 890 %        const PixelInfo *fill,const MagickBooleanType invert,
 891 %        ExceptionInfo *exception)
 892 %
 893 %  A description of each parameter follows:
 894 %
 895 %    o image: the image.
 896 %
 897 %    o target: the RGB value of the target color.
 898 %
 899 %    o fill: the replacement color.
 900 %
 901 %    o invert: paint any pixel that does not match the target color.
 902 %
 903 %    o exception: return any errors or warnings in this structure.
 904 %
 905 */
 906 MagickExport MagickBooleanType OpaquePaintImage(Image *image,
 907   const PixelInfo *target,const PixelInfo *fill,const MagickBooleanType invert,
 908   ExceptionInfo *exception)
 909 {
 910 #define OpaquePaintImageTag  "Opaque/Image"
 911
 912   CacheView
 913     *image_view;
 914
 915   MagickBooleanType
 916     status;
 917
 918   MagickOffsetType
 919     progress;
 920
 921   PixelInfo
 922     conform_fill,
 923     conform_target,
 924     zero;
 925
 926   ssize_t
 927     y;
 928
 929   assert(image != (Image *) NULL);
 930   assert(image->signature == MagickCoreSignature);
 931   assert(target != (PixelInfo *) NULL);
 932   assert(fill != (PixelInfo *) NULL);
 933   if (image->debug != MagickFalse)
 934     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
 935   if (SetImageStorageClass(image,DirectClass,exception) == MagickFalse)
 936     return(MagickFalse);
 937   ConformPixelInfo(image,fill,&conform_fill,exception);
 938   ConformPixelInfo(image,target,&conform_target,exception);
 939   /*
 940     Make image color opaque.
 941   */
 942   status=MagickTrue;
 943   progress=0;
 944   GetPixelInfo(image,&zero);
 945   image_view=AcquireAuthenticCacheView(image,exception);
 946 #if defined(MAGICKCORE_OPENMP_SUPPORT)
 947   #pragma omp parallel for schedule(static) shared(progress,status) \
 948     magick_number_threads(image,image,image->rows,1)
 949 #endif
 950   for (y=0; y < (ssize_t) image->rows; y++)
 951   {
 952     PixelInfo
 953       pixel;
 954
 955     register Quantum
 956       *magick_restrict q;
 957
 958     register ssize_t
 959       x;
 960
 961     if (status == MagickFalse)
 962       continue;
 963     q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
 964     if (q == (Quantum *) NULL)
 965       {
 966         status=MagickFalse;
 967         continue;
 968       }
 969     pixel=zero;
 970     for (x=0; x < (ssize_t) image->columns; x++)
 971     {
 972       GetPixelInfoPixel(image,q,&pixel);
 973       if (IsFuzzyEquivalencePixelInfo(&pixel,&conform_target) != invert)
 974         {
 975           PixelTrait
 976             traits;
 977
 978           traits=GetPixelChannelTraits(image,RedPixelChannel);
 979           if ((traits & UpdatePixelTrait) != 0)
 980             SetPixelRed(image,(Quantum) conform_fill.red,q);
 981           traits=GetPixelChannelTraits(image,GreenPixelChannel);
 982           if ((traits & UpdatePixelTrait) != 0)
 983             SetPixelGreen(image,(Quantum) conform_fill.green,q);
 984           traits=GetPixelChannelTraits(image,BluePixelChannel);
 985           if ((traits & UpdatePixelTrait) != 0)
 986             SetPixelBlue(image,(Quantum) conform_fill.blue,q);
 987           traits=GetPixelChannelTraits(image,BlackPixelChannel);
 988           if ((traits & UpdatePixelTrait) != 0)
 989             SetPixelBlack(image,(Quantum) conform_fill.black,q);
 990           traits=GetPixelChannelTraits(image,AlphaPixelChannel);
 991           if ((traits & UpdatePixelTrait) != 0)
 992             SetPixelAlpha(image,(Quantum) conform_fill.alpha,q);
 993         }
 994       q+=GetPixelChannels(image);
 995     }
 996     if (SyncCacheViewAuthenticPixels(image_view,exception) == MagickFalse)
 997       status=MagickFalse;
 998     if (image->progress_monitor != (MagickProgressMonitor) NULL)
 999       {
1000         MagickBooleanType
1001           proceed;
1002
1003 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1004         #pragma omp critical (MagickCore_OpaquePaintImage)
1005 #endif
1006         proceed=SetImageProgress(image,OpaquePaintImageTag,progress++,
1007           image->rows);
1008         if (proceed == MagickFalse)
1009           status=MagickFalse;
1010       }
1011   }
1012   image_view=DestroyCacheView(image_view);
1013   return(status);
1014 }
1015 \f
1016 /*
1017 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1018 %                                                                             %
1019 %                                                                             %
1020 %                                                                             %
1021 %     T r a n s p a r e n t P a i n t I m a g e                               %
1022 %                                                                             %
1023 %                                                                             %
1024 %                                                                             %
1025 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1026 %
1027 %  TransparentPaintImage() changes the opacity value associated with any pixel
1028 %  that matches color to the value defined by opacity.
1029 %
1030 %  By default color must match a particular pixel color exactly.  However, in
1031 %  many cases two colors may differ by a small amount.  Fuzz defines how much
1032 %  tolerance is acceptable to consider two colors as the same.  For example,
1033 %  set fuzz to 10 and the color red at intensities of 100 and 102 respectively
1034 %  are now interpreted as the same color.
1035 %
1036 %  The format of the TransparentPaintImage method is:
1037 %
1038 %      MagickBooleanType TransparentPaintImage(Image *image,
1039 %        const PixelInfo *target,const Quantum opacity,
1040 %        const MagickBooleanType invert,ExceptionInfo *exception)
1041 %
1042 %  A description of each parameter follows:
1043 %
1044 %    o image: the image.
1045 %
1046 %    o target: the target color.
1047 %
1048 %    o opacity: the replacement opacity value.
1049 %
1050 %    o invert: paint any pixel that does not match the target color.
1051 %
1052 %    o exception: return any errors or warnings in this structure.
1053 %
1054 */
1055 MagickExport MagickBooleanType TransparentPaintImage(Image *image,
1056   const PixelInfo *target,const Quantum opacity,const MagickBooleanType invert,
1057   ExceptionInfo *exception)
1058 {
1059 #define TransparentPaintImageTag  "Transparent/Image"
1060
1061   CacheView
1062     *image_view;
1063
1064   MagickBooleanType
1065     status;
1066
1067   MagickOffsetType
1068     progress;
1069
1070   PixelInfo
1071     zero;
1072
1073   ssize_t
1074     y;
1075
1076   assert(image != (Image *) NULL);
1077   assert(image->signature == MagickCoreSignature);
1078   assert(target != (PixelInfo *) NULL);
1079   if (image->debug != MagickFalse)
1080     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1081   if (SetImageStorageClass(image,DirectClass,exception) == MagickFalse)
1082     return(MagickFalse);
1083   if (image->alpha_trait == UndefinedPixelTrait)
1084     (void) SetImageAlphaChannel(image,OpaqueAlphaChannel,exception);
1085   /*
1086     Make image color transparent.
1087   */
1088   status=MagickTrue;
1089   progress=0;
1090   GetPixelInfo(image,&zero);
1091   image_view=AcquireAuthenticCacheView(image,exception);
1092 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1093   #pragma omp parallel for schedule(static) shared(progress,status) \
1094     magick_number_threads(image,image,image->rows,1)
1095 #endif
1096   for (y=0; y < (ssize_t) image->rows; y++)
1097   {
1098     PixelInfo
1099       pixel;
1100
1101     register ssize_t
1102       x;
1103
1104     register Quantum
1105       *magick_restrict q;
1106
1107     if (status == MagickFalse)
1108       continue;
1109     q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
1110     if (q == (Quantum *) NULL)
1111       {
1112         status=MagickFalse;
1113         continue;
1114       }
1115     pixel=zero;
1116     for (x=0; x < (ssize_t) image->columns; x++)
1117     {
1118       GetPixelInfoPixel(image,q,&pixel);
1119       if (IsFuzzyEquivalencePixelInfo(&pixel,target) != invert)
1120         SetPixelAlpha(image,opacity,q);
1121       q+=GetPixelChannels(image);
1122     }
1123     if (SyncCacheViewAuthenticPixels(image_view,exception) == MagickFalse)
1124       status=MagickFalse;
1125     if (image->progress_monitor != (MagickProgressMonitor) NULL)
1126       {
1127         MagickBooleanType
1128           proceed;
1129
1130 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1131         #pragma omp critical (MagickCore_TransparentPaintImage)
1132 #endif
1133         proceed=SetImageProgress(image,TransparentPaintImageTag,progress++,
1134           image->rows);
1135         if (proceed == MagickFalse)
1136           status=MagickFalse;
1137       }
1138   }
1139   image_view=DestroyCacheView(image_view);
1140   return(status);
1141 }
1142 \f
1143 /*
1144 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1145 %                                                                             %
1146 %                                                                             %
1147 %                                                                             %
1148 %     T r a n s p a r e n t P a i n t I m a g e C h r o m a                   %
1149 %                                                                             %
1150 %                                                                             %
1151 %                                                                             %
1152 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1153 %
1154 %  TransparentPaintImageChroma() changes the opacity value associated with any
1155 %  pixel that matches color to the value defined by opacity.
1156 %
1157 %  As there is one fuzz value for the all the channels, TransparentPaintImage()
1158 %  is not suitable for the operations like chroma, where the tolerance for
1159 %  similarity of two color component (RGB) can be different. Thus we define
1160 %  this method to take two target pixels (one low and one high) and all the
1161 %  pixels of an image which are lying between these two pixels are made
1162 %  transparent.
1163 %
1164 %  The format of the TransparentPaintImageChroma method is:
1165 %
1166 %      MagickBooleanType TransparentPaintImageChroma(Image *image,
1167 %        const PixelInfo *low,const PixelInfo *high,const Quantum opacity,
1168 %        const MagickBooleanType invert,ExceptionInfo *exception)
1169 %
1170 %  A description of each parameter follows:
1171 %
1172 %    o image: the image.
1173 %
1174 %    o low: the low target color.
1175 %
1176 %    o high: the high target color.
1177 %
1178 %    o opacity: the replacement opacity value.
1179 %
1180 %    o invert: paint any pixel that does not match the target color.
1181 %
1182 %    o exception: return any errors or warnings in this structure.
1183 %
1184 */
1185 MagickExport MagickBooleanType TransparentPaintImageChroma(Image *image,
1186   const PixelInfo *low,const PixelInfo *high,const Quantum opacity,
1187   const MagickBooleanType invert,ExceptionInfo *exception)
1188 {
1189 #define TransparentPaintImageTag  "Transparent/Image"
1190
1191   CacheView
1192     *image_view;
1193
1194   MagickBooleanType
1195     status;
1196
1197   MagickOffsetType
1198     progress;
1199
1200   ssize_t
1201     y;
1202
1203   assert(image != (Image *) NULL);
1204   assert(image->signature == MagickCoreSignature);
1205   assert(high != (PixelInfo *) NULL);
1206   assert(low != (PixelInfo *) NULL);
1207   if (image->debug != MagickFalse)
1208     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
1209   if (SetImageStorageClass(image,DirectClass,exception) == MagickFalse)
1210     return(MagickFalse);
1211   if (image->alpha_trait == UndefinedPixelTrait)
1212     (void) SetImageAlphaChannel(image,OpaqueAlphaChannel,exception);
1213   /*
1214     Make image color transparent.
1215   */
1216   status=MagickTrue;
1217   progress=0;
1218   image_view=AcquireAuthenticCacheView(image,exception);
1219 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1220   #pragma omp parallel for schedule(static) shared(progress,status) \
1221     magick_number_threads(image,image,image->rows,1)
1222 #endif
1223   for (y=0; y < (ssize_t) image->rows; y++)
1224   {
1225     MagickBooleanType
1226       match;
1227
1228     PixelInfo
1229       pixel;
1230
1231     register Quantum
1232       *magick_restrict q;
1233
1234     register ssize_t
1235       x;
1236
1237     if (status == MagickFalse)
1238       continue;
1239     q=GetCacheViewAuthenticPixels(image_view,0,y,image->columns,1,exception);
1240     if (q == (Quantum *) NULL)
1241       {
1242         status=MagickFalse;
1243         continue;
1244       }
1245     GetPixelInfo(image,&pixel);
1246     for (x=0; x < (ssize_t) image->columns; x++)
1247     {
1248       GetPixelInfoPixel(image,q,&pixel);
1249       match=((pixel.red >= low->red) && (pixel.red <= high->red) &&
1250         (pixel.green >= low->green) && (pixel.green <= high->green) &&
1251         (pixel.blue  >= low->blue) && (pixel.blue <= high->blue)) ? MagickTrue :
1252         MagickFalse;
1253       if (match != invert)
1254         SetPixelAlpha(image,opacity,q);
1255       q+=GetPixelChannels(image);
1256     }
1257     if (SyncCacheViewAuthenticPixels(image_view,exception) == MagickFalse)
1258       status=MagickFalse;
1259     if (image->progress_monitor != (MagickProgressMonitor) NULL)
1260       {
1261         MagickBooleanType
1262           proceed;
1263
1264 #if defined(MAGICKCORE_OPENMP_SUPPORT)
1265         #pragma omp critical (MagickCore_TransparentPaintImageChroma)
1266 #endif
1267         proceed=SetImageProgress(image,TransparentPaintImageTag,progress++,
1268           image->rows);
1269         if (proceed == MagickFalse)
1270           status=MagickFalse;
1271       }
1272   }
1273   image_view=DestroyCacheView(image_view);
1274   return(status);
1275 }